This is the Nightwind 2, a compact, unmanned aerial vehicle made of carbon fiber. It's powered by an amazing new direct-injected, 88-cc, two-stroke hybrid boxer engine developed by Ricardo, and it's going to change the future of UAVs.

Unmanned aerial vehicles, a.k.a. drones, are not a new enterprise — they've been flying in military applications for years, and have become integral parts of both Air Force and Navy arsenals and key tools in ground-troop operations. Everyone knows the big bad Predator drones that fly mission in the war zones and have the capability to destroy targets remotely, but those require nearly as much ground support as a regular manned aircraft. The cost and complexity of those big drones is driving development in much more user- and taxpayer friendly compact UAVs. The Nightwind is an example of the latter.

These are the first images of the stealthy Predator C Avenger in flight. With a 66-foot wingspan,…
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Portable UAVs generally have a wingspan of less than three meters, lightweight construction, and the appearance of a model aircraft — the latter mostly because many of their parts come from model aircraft. Their strength lies in their size: They can be stored and transported by a single soldier or in a single vehicle, and hand launched using something akin to an oversized sling shot or from atop a moving vehicle. The disadvantages come from their components.

A good number of the engines and electric motors used in UAVs come from the hobby-aircraft industry. While this kind of equipment work greats in civilian toys, it often isn't so fabulous on the battlefield. Weed wacker and lawnmower engines are also used for propulsion, leading to questionable reliability and low power density. Another issue is their reliance on gasoline as a fuel, an expensive handicap in a military supply chain that deals with relatively heavy JP-8 fuel. What electric motors offer in silence and reliability they give up in range and payload capacity, using room in the fuselage for batteries that could house instruments. The hobby-kit nature also leads to pronounced radar, thermal, and acoustic signatures, all of which can lead to easy detection by the bad guys.

The Unmanned Aerial Systems Nightwind 2 is not a hobby aircraft — it's a bad-ass, carbon-fiber flying wing with a 2-meter wingspan, and it has never, not even once, been tracked on radar. Not only is it invisible to radar, but when flying above 6000 feet, it can't be tracked thermally or acoustically. When properly painted, it can't even be seen. The only problem is its range: The Nightwind uses an electric motor for propulsion, which means batteries, which means that, even when fully laden with battery packs, it only offers around 30 minutes of flight time.

This is where engineering firm Ricardo — the same firm that developed the twin-clutch gearbox for the Bugatti Veyron — comes in. Over the last six months, Ricardo partnered with UAS to develop a clean-sheet hybrid engine aimed at offering the best of all worlds. The tiny engine is dubbed Wolverine 3 on account of its Michigan-based development and high power density. It's an air-cooled, two-cylinder, two-cycle, 88-cc, direct-injected, horizontally-opposed boxer with a two-piece aluminum block and anodized Nikasil cylinder liners. The engine accoutrements include an off-the-shelf Magneti Marelli ECU; a mechanical fuel pump delivers JP-8 to the cylinders, which is then ignited by traditional spark plugs. A mechanical oil pump pressurizes a scalable oil tank on top of the engine and feeds both the fuel mix (remember, this is a two-stroke) and total-loss oiling points in the engine. Calling on decades of automotive acoustic-tuning experience, Ricardo has developed an exhaust system capable of silencing the engine to a level below that of the electric motor it replaces.

The real trick is the starter/generator that you don't see in the pictures: It's been adapted from its current application (medical robotics) and mounted on the front of the engine. The motor contributes 500 watts (0.66 hp) to the engine's total output, but more important for military operations, it can act as sole motivation, powering the Nightwind for stealthy, low-level flight. Engine architect Steve Cakebread (yes, he's very, very British) has visions of full hybridization in the future, even using the engine as a range extender a'la Chevrolet Volt.

Because of the Night Wind's sleek, B2-bomberesque profile, the engine needed to be compact, with a design envelope of 6.9 inches of height, 7.5 inches of depth, and 10.5 inches of width. In other words, it's really, really tiny. In the form you see here, the engine weighs all of five pounds; fully trimmed, it tips the scales at a seven pounds. With this engine in place, the Nightwind's operation envelope changes dramatically: Its ceiling increases from 10,000 feet to 20,000 feet, it's silent at 1,000 feet of altitude instead of 6,000 feet, and its operating window increases from 30 minutes to several hours. (The fuel tank is also scalable.)

Still, the brilliance of the program comes down to dollars and cents. Whereas big, exciting systems like the Predator cost millions of dollars per copy and require a maintenance and operations crew, the Nightwind takes a crew of two at most, can be operated anywhere, and costs $65,000. That puts it within reach of the civilian market, something UAS intends to go after. The company's president and CEO, former Pentagon man USAF Colonel Sandy Mangold, envisions it flying high over the U.S.-Mexico border doing surveillance, surveying thousands of miles of roads for possible repairs, watching over oil pipelines, and acting as another tool in the drug enforcement arsenal.

Rick Scudder, director of the University of Dayton Research Institute's Center for UAV Exploitation, puts the system's usefulness into perspective with this example: Say a glue factory catches fire and the fire chief wants to know if it's safe to send his guys into the blaze. A portable UAV can be fitted with a tiny mass spectrometer able to sniff out chemical compositions in the air and report them. Once airborne, the UAV detects the chemical, and data from crafts yaw and pitch sensors can be compared to its GPS flight path and used to determine wind direction and speed, thus telling authorities exactly which neighborhoods to evacuate.

The first Nightwind/Ricardo test flight and Pentagon demonstration is scheduled to take place this summer in Nevada. Both companies expect an enthusiastic response.